In the Feb. 16 SN: Robots roll into the classroom, brain zaps for severe depression, particle colliders of the future, how to walk like a tetrapod, sleepless nights boost Alzheimer's proteins and more.

Which came first: the impact or the eruptions? That question is at the heart of two new studies in the Feb. 22 Science seeking to answer one of the most hotly debated questions in Earth’s geologic history: Whether an asteroid impact or massive volcanism that altered the global climate was mostly to blame for the demise of all nonbird dinosaurs 66 million years ago.

A new dinosaur shows that even Tyrannosaurus rex had humble beginnings.

Dubbed Moros intrepidus, or “the harbinger of doom,” the new species is one of the smallest tyrannosaurs yet discovered from the Cretaceous Period. Analyses of the animal’s fossilized leg show that the creature would have stood only 1.2 meters at the hip, and weighed an estimated 78 kilograms — about the size of a...

A 240-million-year-old case of bone cancer has turned up in a fossil of an extinct ancestor of turtles. Dating to the Triassic Period, the fossil is the oldest known example of this cancer in an amniote, a group that includes mammals, birds and reptiles, researchers report online February 7 in JAMA Oncology.

The fossilized left femur from the shell-less stem-turtle Pappochelys rosinae...

When it comes to deciding what’s for breakfast, lunch or dinner, pandas have it easy: Bamboo, bamboo and more bamboo. But that wasn’t always the case.

Although modern giant pandas (Ailuropoda melanoleuca) chow almost exclusively on bamboo in the mountain forests of central China, these bears’ diet was much broader not so long ago, researchers report online January 31 in Current Biology....

Two newly found specimens of the mysterious, platypus-like reptile suggest that the ancient creature had very small eyes for its size, and may have hunted mainly by touch. That makes E. carrolldongi the oldest known amniote — a group that includes reptiles and mammals — to use a sense other than sight to find its prey, scientists...

Much to their surprise, scientists in Antarctica have uncovered what appear to be remnants of tiny animals in mud dredged from a lake that has been covered by a thick mantle of ice for thousands of years.

The researchers on this expedition — known as the Subglacial Antarctic Lakes Scientific Access, or SALSA — are the first to sample Lake Mercer, a body of water about 600 kilometers from...

Orobates pabsti lived between 280 million and 290 million years ago, but it was pretty advanced at doing the locomotion.

Using computer simulations, re-created skeletons, fossil trackways and a walking robot dubbed the OroBOT, scientists found that this ancient four-footed creature had a surprisingly efficient gait. The result suggests that developing a more advanced way of walking may...

Here’s our short list of discoveries reported in 2018 that could shake up science, if they hold up.

Not so standard

Dangling from a helium balloon high above Antarctica, the ANITA detector spied two odd signals that hint at the existence of new subatomic particles. Such extremely energetic particles, if they exist, could upend the standard model, the theory that describes the elementary...

Think of pterosaurs, the flying reptiles that were distant cousins to the dinosaurs, and you may imagine a fearsome, leathery, winged creature. But new fossil evidence suggests at least some pterosaurs were soft and fluffy, covered in a diverse array of fibrous structures including possible precursors of feathers, scientists report online December 17 in Nature Ecology & Evolution.

A collection of roughly 255-million-year-old fossils suggests that three major plant groups existed earlier than previously thought, and made it through a mass extinction that wiped out more than 90 percent of Earth’s marine species and roughly 70 percent of land vertebrates.

The fossils, described in the Dec. 21 Science, push back the earliest...